SEOUL, SOUTH KOREA (AP) - Computer networks at major South Korean banks and top TV broadcasters crashed en masse Wednesday, paralyzing bank machines across the country and prompting speculation of a cyberattack by North Korea.
Screens went blank at 2 p.m. (0500 GMT), with reports of skulls popping up on some computer screens, the state-run Korea Information Security Agency said _ a strong indication that hackers planted a malicious code in South Korean systems. Some computers came back online more than 2 1/2 hours later.
Police and South Korean officials couldn’t immediately determine the cause. But experts said a cyberattack orchestrated by Pyongyang was likely to blame. The rivals have exchanged threats following U.N. sanctions meant to punish North Korea over its nuclear test last month.
The shutdown appeared to be more of an inconvenience than a source of panic. There were no immediate reports that bank customers’ records were compromised. It also didn’t affect government agencies or networks essential to the country’s infrastructure, such as power plants or transportation systems.
Still, it raised worries about the overall vulnerability to attacks in South Korea, a world leader in broadband speed and mobile Internet access. Previous hacking attacks at private companies compromised millions of people’s personal data. Past malware attacks also disabled access to government agency websites and destroyed files in personal computers.
The shutdown comes amid rising rhetoric and threats of attack from Pyongyang in response to U.N. punishment for its December rocket launch and February nuclear test. Washington also expanded sanctions against North Korea this month in a bid to cripple the regime’s ability to develop its nuclear program.
North Korea has threatened revenge for the sanctions and for ongoing routine U.S.-South Korean military drills it considers rehearsals for invasion.
Seoul believes North Korea runs an Internet warfare unit aimed at hacking U.S. and South Korean government and military networks to gather information and disrupt service.
Seoul blames North Korean hackers for several cyberattacks in recent years. Pyongyang has either denied or ignored those charges. Hackers operating from IP addresses in China have also faced blame.
The latest network paralysis took place just days after North Korea accused South Korea and the U.S. of staging a cyberattack that shut down its websites for two days last week. Loxley Pacific, the Thailand-based Internet service provider, confirmed the outage but did not say what caused the shutdown in North Korea.
Shinhan Bank, a major South Korean lender, reported a two-hour system shutdown Wednesday, including online banking and automated teller machines. It said networks later came back online, and that banking was back to normal at branches and online. Shinhan said no customer records or accounts were compromised.
The other bank, Nonghyup, also a major lender, said its system eventually came back online. Officials didn’t answer a call seeking details on the safety of customer records.
Jeju Bank said some of its branches also reported network shutdowns.
At one Starbucks in downtown Seoul, customers were asked to pay for their coffee in cash, and lines were forming outside disabled bank machines. Seoul is a largely cashless city, with many people relying on debit and credit cards to pay for goods and services.
Broadcasters KBS and MBC said their computers went down at 2 p.m., but officials said the shutdown did not affect daily TV broadcasts. Computers were still down more than three hours after the shutdown began, the news outlets said.